Petroleum industry producing emulsions

Leopold, G. Breaking Produced-Fluid and Process-Stream Emulsions in Emulsions, Fundamentals and Applications in the Petroleum Industry, Schramm, L.L., Ed., American Chemical Society Washington, DC, 1992, pp. 342-383. 

Within the petroleum industry, emulsion of oil and water may be associated with every stage of production, transportation, or refining. The extent of emulsification and the economic impact of contaminants associated with emulsions in hydrocarbon-processing equipment will determine what treating methods, if any, are necessary to produce desired hydrocarbon specifications. An understanding of the impact of oil contaminants and incomplete demulsification on key hydrocarbon processing areas is required. The prime areas of concern are typically... 

Some surface emulsions are desirable in the petroleum industry. For example, conventional heavy-crude oil can be transported by pipeline if it is formulated as an O/W emulsion (see Section 11.4.4). Another kind of surface emulsion that is desirable is the Orinoco bitumen emulsion produced from in situ steam stimulation and recovery in the Orinoco River deposit in Venezuela. This emulsion is reformulated into Orimulsion , an O/W emulsion, containing about 30% fresh water and a stabilizing surfactant (typically about 0.1% each of monoethanolamine and an alcohol ethoxylate) [163-165]. The O/W emulsion has a viscosity of about 450 mPa s (30 °C, 100 s ) compared with the original bitumen viscosity of about lOOOOmPa-s [165, 166]. This emulsion can be used as an alternative fuel for power-generating plants. Being water continuous, the emulsion is easily handled and transported, but otherwise behaves similar to fuel oil. 

An extensive variety of chemical demulsifiers are available to enhance resolution of the water-in-od emulsion that is produced at the wellhead These demulsifiers are simply surfactants that are used to counteract the effect of surfactants naturally present in the wellhead or process emulsions, and which stabilize the water in the oil phase. In the petroleum industry, emulsions of oU in water are known as reverse emulsions. Demulsifiers are also used to destabilize these oil-in-water emulsions. The wide variety of oU types and produced water chemistries in petroleum industry emulsions necessitates an even wider variety of chemical demulsifiers. In addition, production and processing variables require demulsification chemicals tailored to particular process needs. 

Characteristics commonly linked to w/o emulsions are the API gravity, total acidity index (TAI) and asphaltene content (Muller et al, 2009). In the petroleum industry, most of emulsions produced is of type A/O. Figure 13 illustrates an emulsion W/O, where water droplets are dispersed in oil. It is observed from this figure that stable emulsions are characterized by properties that prevent the coalescence of small drops of water, while in unstable emulsions the water droplets coalesce rapidly. 

When oil is recovered from sedimentary formations by conventional means, more than one-half of it can be left behind in the rock (48). This oil is very difficult to remove because it is coating the rock surfaces and not free-flowing. Surfactant-based systems have been developed to enhance the recovery of the trapped oil. When these surfactant solutions are pumped underground, they appear to form microemulsions, bicontinuous structures, and possibly very fine macroemulsions, with the oil. The flow properties of these emulsions through porous media are quite important, therefore much elfort has been invested in rheological studies (49). Once the emulsified oil is removed from the ground, the emulsion needs to be broken in order for the oil to be recovered from the process stream. Another application of emulsions in the petroleum industry is to produce relatively low viscosity emulsions of viscous crude oil to make pipeline transport much easier. 

JMULSIONS CAN BE FOUND IN ALMOST EVERY PART of the petroleum production and recovery process in reservoirs, produced at wellheads, in many parts of the refining process, and in transportation pipelines. In each case the presence and nature of emulsions can determine both the economic and technical successes of the industrial process concerned. This book is intended to provide an introduction to the nature, occurrence, handling, formation, and breaking of petroleum emulsions. The primary focus is on the applications of the principles and includes attention to practical emulsion problems. 

Emulsions, foams, suspensions and aerosols occur, or are created, throughout the full range of processes in the petroleum producing industry (see Table 11.1), including drilling and completion, fracturing and stimulation, reservoir recovery. 

Finally, recycling activities produce small quantities of vanadium pentoxide. The source material used comes from spent catalysts from the petrochemical industry and fly ash, the later being produced by the combustion of oil emulsion in thermal power stations. Commercial production of vanadium from petroleum is promosing as an important source of the element. 

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